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\begin{tabular}{lcccc} \hline
 & (1) & (2) & (3) & (4) \\
VARIABLES & mp\_igos\_joined & formals\_sum\_joined & informals\_sum\_joined & total\_sum\_joined \\ \hline
 &  &  &  &  \\
mp\_igos\_sum & 0.001 &  &  &  \\
 & (0.003) &  &  &  \\
Democratization & 0.337** & 0.314** & 0.032 & 0.294** \\
 & (0.101) & (0.100) & (0.046) & (0.114) \\
Autocratization & -0.125 & -0.084 & 0.021 & -0.015 \\
 & (0.086) & (0.078) & (0.038) & (0.090) \\
StableDemoc & 0.245** & 0.229** & 0.052 & 0.368** \\
 & (0.073) & (0.059) & (0.057) & (0.074) \\
Dispute & -0.054** & -0.023 & -0.008 & -0.023 \\
 & (0.018) & (0.017) & (0.011) & (0.020) \\
Hegemony & -23.114** & -21.766** & 4.631 & -17.380+ \\
 & (7.392) & (8.167) & (3.578) & (9.321) \\
Year & -0.059** & -0.057** & 0.022* & -0.034 \\
 & (0.018) & (0.020) & (0.009) & (0.023) \\
FormerCommunist & 0.988** & 0.907** & 0.480** & 1.429** \\
 & (0.199) & (0.196) & (0.156) & (0.228) \\
Independence & 0.001 & 0.001 & 0.001* & 0.002+ \\
 & (0.001) & (0.001) & (0.001) & (0.001) \\
reg\_mp = 1, North America & -0.248 & -0.355** & -0.183+ & -0.351* \\
 & (0.160) & (0.119) & (0.095) & (0.156) \\
reg\_mp = 2, South America & -0.250 & -0.435** & -0.280** & -0.589** \\
 & (0.153) & (0.123) & (0.095) & (0.167) \\
reg\_mp = 3, Middle East & -0.107 & -0.300* & 0.025 & -0.365* \\
 & (0.138) & (0.137) & (0.052) & (0.152) \\
reg\_mp = 4, Asia & -0.308* & -0.355* & -0.008 & -0.191 \\
 & (0.145) & (0.140) & (0.056) & (0.150) \\
reg\_mp = 5, Oceania & -0.539** & -0.462** & -0.073 & -0.353* \\
 & (0.154) & (0.161) & (0.088) & (0.160) \\
reg\_mp = 6, Europe & -0.391* & -0.488** & 0.091 & -0.297 \\
 & (0.154) & (0.144) & (0.099) & (0.194) \\
formals\_sum\_member &  & 0.014** &  &  \\
 &  & (0.003) &  &  \\
informals\_sum\_member &  &  & 0.065** &  \\
 &  &  & (0.008) &  \\
total\_sum\_member &  &  &  & 0.026** \\
 &  &  &  & (0.003) \\
Constant & 124.627** & 118.325** & -44.642* & 71.325 \\
 & (37.813) & (42.194) & (18.257) & (47.854) \\
 &  &  &  &  \\
Observations & 4,665 & 4,665 & 4,665 & 4,665 \\
R-squared & 0.051 & 0.085 & 0.410 & 0.220 \\
Number of ccode & 173 & 173 & 173 & 173 \\
 N & 4665 & 4665 & 4665 & 4665 \\ \hline
\multicolumn{5}{c}{ Standard errors in parentheses} \\
\multicolumn{5}{c}{ ** p$<$0.01, * p$<$0.05, + p$<$0.1} \\
\end{tabular}
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